A convicted killer has successfully challenged the home secretary's power to intervene in sentencing and extend a prisoner's minimum life term.

BBC home affairs correspondent Rory Maclean looks at the implications of the case for other "whole life" prisoners.

Who has brought the case and how?

Anthony Anderson, who was convicted of two murders in 1988. The judge at his trial recommended that he serve a minimum term of 15 years before he could be considered for parole.

This was increased to 20 years by the then home secretary.

Anderson successfully argued that this breached the Human Rights Convention which suggests that sentencing is a matter for the courts and not politicians.

What are the implications?

Over 500 prisoners in England and Wales have had their minimum prison sentences increased by the home secretary.

About 70 are in the period between the sentence suggested by the judge at their trials, and the time imposed by the home secretary.

They would be able to ask for the parole board to consider their release now that Anderson has won his case.

How else have European Human Rights laws impacted on British legislation?

The home secretary has already lost the power to set minimum sentences in cases involving juveniles or where life has been imposed for crimes other than murder.

He also cannot now overrule the parole board in these cases.

Why was the government keen to maintain its power to fix minimum sentences?

The government argues that the home secretary's power is within the Human Rights Convention and that it is important that a democratically elected politician has a role in some of the most serious cases in the criminal justice system.

However in both Scotland and Northern Ireland, changes have been made to take politicians out of the system and allow judges alone to decide.